The invention relates to the technology of displaying the identity (number and/or name) of a calling subscriber, i.e. subscriber A at the terminal of a called subscriber, i.e. subscriber B, while subscriber B roams in a visited network.
In the technology used in the GSM system, the number of subscriber A is transmitted to the terminal of subscriber B in call set-up. In response to the number, subscriber B can decide whether or not to answer the call. A mobile station may be able to improve this function by converting the number of subscriber A into a name, provided said name/number combination is stored in the memory of the mobile station.
One of the problems in the above arrangement is that when subscriber B is roaming in the area of a visited network, subscriber B is usually unable to see the number of subscriber A, or this at least requires special inter-operator contracts.
It is thus an object of the invention to provide a method and equipment for implementing the method for transmitting the number or name of subscriber A to the centre of a visited network serving subscriber B, regard special inter-operator contracts. The objects of the invention are achieved by a method and equipment characterized by what is disclosed in the independent claims. The preferred embodiments of the invention are disclosed in the dependent claims.
The invention is based on complementing call set-up by means of intelligent network technology. An intelligent network element, e.g. a separate service control point, is provided with an intelligent network service for controlling said network element:
to receive from a gateway centre the identities of subscriber A and subscriber B and the address of a second centre serving subscriber B, and
to transmit to the second centre a command to transmit the identity of subscriber A to subscriber B""s mobile station via a rapid connection that does not require set-up of a speech connection, so that subscriber B does not have to pay for the call unless he answers it.
According to a preferred embodiment of the invention, the intelligent network service controls said network element to receive and analyze the response of subscriber B relayed by the second centre and, on the basis of the response, to transmit to the first centre instructions necessary for call set-up, disconnection or deflection to subscriber C.
It is an advantage of this embodiment that the identity (name and/or number) of subscriber A is visible on the display of subscriber B""s mobile station regardless of special inter-operator contracts and without speech connection set-up. Subscriber B gains the most advantages from the invention, since he sees the identity of subscriber A and is able to decide in advance whether or not to answer a call. The advantages provided by the invention to operators include first of all a chance to display the identity of subscriber A without special contracts. Another advantage to an operator and to subscriber A is that subscriber B will answer at least some calls, since in prior art systems many users take no calls at all abroad because of the expensive long-distance calls.